BeautifulSoup find_all 函数在 main 中不起作用

Question

我正在尝试在网站 conforama 上删除，为此，我正在使用 BeautifulSoup。我正在尝试检索商品的价格、描述、费率、url 和评论数量，并在 3 个页面上递归执行此操作。

首先，我导入了所需的库

import csv
from bs4 import BeautifulSoup
import pandas as pd
from selenium import webdriver
from webdriver_manager.chrome import ChromeDriverManager

我定义了第一个函数：get_url 它将使用特定的 search_term 和 return 正确地格式化 url 和等待的 url格式正确的页码

def get_url(search_term):
    template = 'https://www.conforama.fr/recherche-conforama/{}'
    
    search_term = search_term.replace(' ','+')
    
    url = template.format(search_term)
    
    url+= '?P1-PRODUCTS%5Bpage%5D={}'
    
    return url

我定义了第二个来去除一些使数据不可读的内容

def format_number(number):
    new_number = ''
    for n in number:
        if n not in '0123456789€,.' : return new_number
        new_number+=n

我定义了第三个函数，它将记录并从中提取我需要的所有信息：它的价格、描述、url、评分和评论数量。

def extract_record(item):
    print(item)
    descriptions = item.find_all("a", {"class" : "bindEvent"})

    description = descriptions[1].text.strip() + ' ' + descriptions[2].text.strip()

    #get url of product
    url = descriptions[2]['href']
    print(url)

    #number of reviews
    nor = descriptions[3].text.strip()
    nor = format_number(nor)

    #rating
    try:
        ratings = item.find_all("span", {"class" : "stars"})
        rating = ratings[0]['data']
    except AttributeError:
        return

    #price
    try:
        prices = item.find_all("div", {"class" : "price-product"})
        price = prices[0].text.strip()
    except AttributeError:
        return
    price = format_number(price)
    
    return (description, price, rating, nor, url)

最后，我将所有函数集中在一个主函数中，这将使我能够遍历我需要从中提取的所有页面

def main(search_term):
    #product_name = search_term
    
    driver = webdriver.Chrome(ChromeDriverManager().install())
    records = []
    url = get_url(search_term)
    somme = 0
    for page in range (1,4):
       driver.get(url.format(page))
       soup = BeautifulSoup(driver.page_source, 'html.parser')
       print('longueur soup', len(soup))
       print(soup)
       results = soup.find_all('li', {'class' : 'ais-Hits-item box-product fragItem'})
       print(len(results))
       somme+=len(results)
       for result in results:
           record = extract_record(result)
           if record:
               print(record)
               records.append(record)
    driver.close()
    print('somme',somme)

现在的问题是，当我运行所有命令一一执行时：

driver = webdriver.Chrome(ChromeDriverManager().install())
url = get_url('couch').format(1)
driver.get(url)
soup = BeautifulSoup(driver.page_source, 'html.parser')
results = soup.find_all('li', {'class' : 'ais-Hits-item box-product fragItem'})
item = results[0]
extracted = extract_record(item)

一切都很好，extract_record 函数 return 正是我需要的。但是，当我运行主函数时，这行代码：

results = soup.find_all('li', {'class' : 'ais-Hits-item box-product fragItem'})

没有return任何结果，即使我知道当我在主函数之外执行它时它有结果

有没有人遇到同样的问题，你知道我做错了什么以及如何解决吗？非常感谢阅读和尝试回答

Answer 1

会发生什么？

主要问题是元素需要一些时间来生成/显示，并且在您抓取 driver.page_source 的那一刻它们不可用。

如何修复？

使用seleniums waits直到找到特定元素：

wait = WebDriverWait(driver, 10)
wait.until(EC.presence_of_element_located((By.CSS_SELECTOR, 'li.ais-Hits-item.box-product.fragItem div.price-product')))
soup = BeautifulSoup(driver.page_source, 'html.parser')
results = soup.find_all('li', {'class' : 'ais-Hits-item box-product fragItem'})

例子

...
from selenium import webdriver
from webdriver_manager.chrome import ChromeDriverManager
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

...

def main(search_term):
    #product_name = search_term
    
    driver = webdriver.Chrome(ChromeDriverManager().install())
    records = []
    url = get_url(search_term)
    somme = 0
    for page in range (1,4):
        driver.get(url.format(page))
        print(url.format(page))
        wait = WebDriverWait(driver, 10)
        wait.until(EC.presence_of_element_located((By.CSS_SELECTOR, 'li.ais-Hits-item.box-product.fragItem div.price-product')))
        soup = BeautifulSoup(driver.page_source, 'html.parser')
        results = soup.find_all('li', {'class' : 'ais-Hits-item box-product fragItem'})
        somme+=len(results)
        for result in results:
            record = extract_record(result)
            if record:
                print(record)
                records.append(record)
    driver.close()
    print('somme',somme)

main('matelas')

BeautifulSoup find_all 函数在 main 中不起作用

BeautifulSoup find_all function doesn't work inside of main

python

beautifulsoup

web-scraping

python-3.x

会发生什么？

如何修复？

例子